{  Statement: http://acmp.ru/?main=task&id_task=66
   Verdict: Accepted
}
uses
        SysUtils, Math;

const
    s = 'qwertyuiopasdfghjklzxcvbnm';

var
    i,x:longint;
    ch:char;

begin
reset(input,'input.txt');
rewrite(output,'output.txt');
if length(s) <> 26 then assert(false);
read(ch);
for i:=1 to 26 do
    if s[i] = ch then begin
        x := i;
        break;
    end;
write(s[x mod 26 + 1]);
end.